<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="./jq-3.6.0.js"></script>
</head>

<body>
    <div class="big">
        <div>
            <div>1</div>
            <div>2</div>
        </div>
        <div></div>
        <div></div>
        <div></div>
    </div>

</body>
<script>
    //只获取子级的元素
    var bigChild = $('.big>div');
    console.log(bigChild);
    var bigDiv = $('.big div');
    console.log(bigDiv);
</script>

</html>